Pressure actuated switch and plug assembly



Nov. 14, 1967 B. R. REUTEFQ 3,352,9 4

PRESSURE ACTUATED SWITCH AND PLUG ASSEMBLY Filed April 14, 1966 BRIAN R-PEUTE/P INVENTOR United States Patent 3,352,984 PRESSURE ACTUATED SWITCH AND PLUG ASSEMBLY Brian R. Renter, Houston, Tex., assignor to Consolidated Engineering Company, Houston, Tex. Filed Apr. 14, 1966, Ser. No. 544,353 Claims. (Cl. 20083) This invention relates to a pressurized switch and plug assembly of the type which includes in assembled relationship a switch means and a pressure sensitive control means adapted to be insertably connected into the plug in manner to complete connection to the source of pressurized gas which actuates the switch moving control means, and in manner to connect the conductors switching circuits within the switch to the respective negative and positive sides of sources of electrical power.

It is thus a primary object of this invention to provide an assembled switch and pressure sensitive control means, with the assembly being adapted for insertion in a plug means in manner to connectably complete switch and plug assembly while completing connection to a source of pressurized gas and with conductors to sides of a source of electrical power.

It is also an important object of this invention to provide a switch and plug assembly of this class in which a plurality of prongs extend from the switch and control means assembly to comprise insertable connection means with the plug, with insertion being selective in manner that selective prongs comprising conductors to the switch means connect with corresponding conductors from the respective sides of a source of electrical power.

It is yet a further object of this invention to provide a switch and plug assembly of this class adapted to permit assembled switch and control means to be withdrawn from the plug so that valve means in the actuating pressurized gas conduit through the plug may close to prevent escape of the gas during such disconnection.

It is still a further object of the invention to provide a switch and plug assembly of this class in which the control and switch assembly includes an index tab whereby a plurality of prongs insertable into the plug to establish frictional connection therewith may be oriented so that those prongs additionally carrying current from the switch connect with corresponding conductors into the plug.

Other and further objects will be apparent when the specification herein is considered in connection with the drawings, in which:

FIG. 1 is a small scale elevational view showing a switch and plug assembly in relation to an appropriately supported plug and with a pressurized gas conduit be ing shown in relation to the assembly;

FIG. 2 is a large scale sectional elevational view showing details of a switch and plug assembly correspondingly as shown to small scale in FIG. 1;

FIG. 3 is a bottom view taken along lines 33 of FIG. 2; and

FIG. 4 is a conventional diagram of a single pole, double throw switch corresponding with the switch indicated as being encased in FIG. 2.

Referring now in detail to the drawings in which like reference numerals are applied to like elements in the various views, a pressure actuated switch and plug assembly It), as shown in FIG. 1, includes an assembly case or housing 11 which is supported upon, and connected into, a plug 12 which is in turn supported by a plate, wall or base 13. The switch within the housing 11 functions in correspondence with the switch 50 shown in FIG. 1 of co-pending application Ser. No. 518,353 for Self-Purging Pneumatic Conveying Apparatus, filed of even date with this application, and correspondingly 1 externally threaded conductors 14a, 15a and 16a, as shown in FIG. 1, can connect respectively with a negative source and two parallel positive source conductor lines.

A conduit 17 conveys a pressurized gas, as air, from a T 18 in a compressed gas or air conduit 19, upwardly to actuate the switch, as will be hereinbelow described. Such a compressed gas or air conduit 19 may correspond functionally with any conduit which conveys an operative gas or compressed air, as for instance the operative air conduit shown in FIG. 1 of the aforesaid co-pending application Ser. No. 518,353 for Self-Purging Pneumatic Conveying Apparatus filed of even date herewith.

The assembly housing 11 includes a base or bottom closure 20 which includes lowermost a metallic box 21 which seats upon the plug 12, the box being of rectangular cross-section as indicated in FIG. 3. A comparatively large central bore 23 is provided through the bottom of a metallic box 21 as indicated in FIGS. 2 and 3. A plastic or insulative base 24 seats within the metallic box 21, and oppositely disposed connection blocks 25, as of metal, are provided whereby the box 21 may be securely connected to the assembly housing 11, as by machine screws 26 which pass through the housing 11 and box 21 and threadably into the connection blocks 25.

The base block 27 of a bellows housing 28, to be hereinbelow described, seats centrally upon the upper surface of the plastic base 24 and a compressed gas commnnication tube 29 is threadably connected centrally into the base block 27 while the plastic base 24 may be moulded around the tube 29 which further extends downwardly through the bore 23 in the bottom of the box 21.

The compressed gas conduit 17, which includes the conduit 31 from the T 18, also includes an upper member or tubular head 30 which seats within the plug 12 and which therebelow passes threadably through the plug and extends downwardly therebelow as the uppermost member of the aforesaid compressed gas conduit 17, and into which the conduit tubular lower member 31 is threadably connected.

The tube 29 has a bore 32 passing centrally downwardly thereinto to communicate with lateral ports 33 provided slightly above the closed lower end of the tube. Also, the tube 29 has an annular groove around a part thereof which slides in the conduit head member 30, an O-ring 34 being provided in the annular groove to insure closably sealed communication between the compressed gas conduit 17 and the interior of the bellows housing 28 thereabove.

A plurality (preferably eight) of metallic tubes or prongs 35 are molded into, or tightly fitted through the plastic base 24 and extend downwardly therebelow, bores 36 being provided in the plug 12 to receive the prongs. Metallic conductor tabs extend upwardly from the under surface of the plug 12 and into the plug to make metallic or electrical contact with the prongs 35, three of the four tabs shown in FIG. 2 being indicated by the respective reference numerals 14a, 15a and 16a. Insulated conductors 14b, 15b and 16b, to be further described hereinbelow, have the lower ends of their metallic conductor wires soldered into respective prongs 35 which communicate with, or carry circuit to the respective tabs 14a, 15a and 16a. A material as Chico, or a plastic as epoxy, or any suitable hardenable substance 37 is provided within the housing 11 to fill the space above the plastic base 24 up to the level of the tops of the blocks 25 and around the bellows assembly base block 27 and such substance 37 hardens about the blocks 25 and molds thereinto the insulated lower end portions of the respective conductors 14b, 15b and 16b.

The bellows housing 28 includes a central member or body 38 having the lower end thereof bored upwardly and for connection into the aforesaid inner Cylindrical upper portion its upper end 42 connected, as by brazing, to the inner wall or surface of the housing body 38; the bellows extending downwardly and then being recurved to extend upwardly, as best shown in FIG. 2. The inner upper part of the bellows 41 include an annular part 43 to provide a shoulder and a cylindrical portion 44 having a closed upper end which extends upwardly centrally from the annular shoulderv 43.

The upper end of the bellows housing body 38 has internal threads 45 therein to threadably receive the externally threaded lower end of an adjustment gland 46 which is counterbored so that the upper end of a spring 47 may seat therein, the lower end of the spring 47 bearing upon an annular disc 48 which is bored to receive the bellows upper end 44 therethrough while the disc 48 seats upon the bellows shoulder 43.

A closure plunger 50 extends slidably sealably through a bore 49 provided in the gland 46, the lower end of such plunger seating upon the closed upper end of the bellows 44. A single pole, double throw switch 51 is indicated occupying the upper part of the space within the casing or assembly housing 11 and such switch 51 may include a bracket 52 supported by the bellows housing 38, or optionally, or additionally the casing 53 of the switch 51 may be located, and/or supported by screws 54 extending inwardly from the housing or casing '11. 1

The single pole, double throw switch 51, indicated in FIG. 2, is shown diagrammatically in FIG. 4 as including a post 56 from which extends a first conductor, as the insulated conductor 14b, also a switch arm 57 is indicated as being pivotally mounted on the post 56. Also, an upper post 58 and a lower post 59 are included to provide respective upper and lower contacts 60, 63, from which extend, respectively, the insulated conductors 15b, 16b.

The posts 56, 57 and 59 are shown in FIG. 2 as extending above the switch casing 53, and as having the respective insulated conductors 14b, 15b and 16b extending therefrom, such conductors, as aforesaid, being shown lower in FIG. 2 as they enter the putty or hardenable material 37 of the base assembly 20.

A snap action plunger 61, indicated diagrammatically in FIG. 4, bears upwardly against the pivoted switch arm 57 and downwardly provides a point 62, also as shown in FIG. 2, which is contacted by the bellows actuated closure plunger 50, as will be hereinbelow described.

The upper member or conduit head 30 of the compressed gas conduit 17 has an externally threaded tubular valve 64 threadably received thereinto, such valve body providing a seat 65 therein, while a seating element 66 extends through the hollow valve 64 so that a head 67 at the upper end of the stem bears against the lower end face of the tube 29 thus to maintain the seating element 68 unseated under normal operative conditions, and until such time as the tube 29, comprising part of the assembly above the plug 12, may be removed, as for repair or disassembly. However, when such tube 29 is removed, the valve element 68 on the valve stem 66 may seat upwardly against the valve seat 65, and thus prevent escape of any compressed gas from the conduit 17.

The plurality of tubes or prongs 35 hereinabove described as extending downwardly from the plastic base 24 of the base assembly or bottom closure 20 are equally engularly spaced apart and equally radially distant from a central, vertical axis through the base, as best indicated in FIG. 3. Also, as shown in black .in FIG. 3, only certain of these prongs 35 are used to have the conductor wires from the insulative conductors 14b, 15b, 16b, from the switch 51 thereabove, electrically connected thereinto, while the other tubes or prongs serve only as frictionally 4 engaging connection members within the bores through the plug 12.

As indicate-d in FIG. 3, the prongs 35 are numbered consequently from No. l to No. 8 in a clockwise direction. Forthis reason an index tab 55 is shown in FIG. 3 extending radially inwardly into the metallicbox bottom bore 23. This tab 55 may be used to orientate the relative positions of the numbered prongs in assembly, and as shown in FIG. 3 it is disposed between the prongs No. 1 and No. 8. correspondingly, as these prongs are inserted into the respectively numbered bores or receptacles in the plug 12, it may be known that prongs No. 2, No. 5 and No. 7, indicated in black in FIG. 3, are inserted in a proper plug bore 36 to carry electrical circuit to those respective tabs 14a, 15a and 16a which have been wired to connect with predetermined circuits, as from a negative and parallel positive sides of a source of electrical power.

The invention is not limited to specific combinations of assemblies of bellows housings with snap action, single pole, double throw switches, but rather includes various embodiments and modifications of assembled switches and control housings. Thus a considerable number of leads in excess of three may extend from the switch assembly, nor is the invention limited to a diaphragm or a bellows as the control means for transmitting gas pressure to operate switch opening and closing. Rather many various arrangements of switches and controls are considered which have a gas conduit means and conductor prongs extending from an assembly base to be guidably insertable respectively into the gas conduit through a plug and into selected respective circuit conductor means from a source of electrical power.

As the invention stands, in synthesis, it includes various combinations of switches and actuating means therefor in assembly and adaptable for respective insertable assembly with various combinations and variations of plugs supplied with electrical power and receiving gas conduit means thereto as long as such may fall within the broad spirit of the invention and within the broad scope of interpretation claimed for, and merited by, the appended claims.

What is claimed is:

1. A pressure actuated switch and plug assembly supporting therein a switch arm having a pivoted end, upper and lower, spaced apart contacts, and at least first, second and third conductors extending respectively from said pivoted end and from said contacts, and a snap action plunger having outwarly a contact point, a bellows housing having a bellows across the housing interior, a bored gland adjustably threadable downwardly into said bellows housing to bear upon a spring provided between said gland and said bellows, a closure plunger extending sealably through said gland bore, an insulative base to receive said bellows housing therein, said conductors connecting with respective conductor prongs extending from said base, an insulative plug supported to connectably receive said prongs therein to contact respective predetermined circuit completing means extending therefrom, a compressed gas conduit connecting upwardly through said base into said bellows housing, a compressed gas communication tube successively connected with said bellows housing and with said base and extending downwardly therebelow into said compressed gas conduit, whereby said bellows moves upwardly and downwardly responsive respectively to increase and decrease of compressed gas pressure so that said closure plunger respectively contacts said point to urge said snap action plunger to pivot said arm to said upper contact to complete first and second conductor circuit, and said snap action plunger acts downwardly and pivots said arm to lower contact to complete first and thirdconductor circuit.

2. A pressure actuated switch and plug assembly as claimed in claim 1 in which said switch arm, contacts and snap action plunger are enacted together, and which additionally comprises a housing including said base removably connected thereto, and which encloses the aforesaid switch element casing and said bellows housing.

3. A pressure actuated switch and plug assembly as claimed in claim 1 in which a plurality of prongs including said conductor prongs extend in circular arrangement from said base, and in which said base provides an indexing tab with relation to which the conductor prongs of said circle may be orientated thereby to connect with the circuit completing means extending from said plug.

4. A pressure actuated switch and plug assembly as claimed in claim 1 which includes in excess of two contacts and conductors therefrom with the contacts each closed and broken by movement of switch arm means.

5. A pressure actuated switch and plug assembly as claimed in claim 1 which additionally comprises an upwardly seating valve in said compressed gas conduit normally held open by contact with said communication tube and closed by compressed gas pressure when said communication tube may be removed.

6. A pressure actuated switch and plug assembly as claimed in claim 1 in which said base comprises lowermost a metallic box to seat on said plug and having a central bore through the "bottom for extension of said prongs and said communication tube therethrough, said base being of plastic immediately above said bottom within said box and being comprised of a hardenable material uppermost around said bellows housing and to mould around said conductors and around metal connection blocks through which said box is connected with an outer housing over said bellows housing and said switch parts and including said base.

7. A pressure actuated switch and plug assembly as claimed in claim 1 in which said base is connected to said plug by a plurality of prongs including said conductor prongs, each comprising a metallic tube restrained in said base, with the wires of said conductors being soldered into selective prongs. v

8. A pressure actuated switch and plug assembly as claimed in claim 1 in which said bellows extends down wardly from the wall of said bellows housing and is then recurved upwardly to provide a central upstanding projec tion on which heats said closure plunger.

9. A pressure actuated switch and plug assembly as claimed in claim 1 in which said assembly includes an outer housing for said switch parts and said bellows housing, and in which said switch parts are encased in a casing rigidly disposed with relation to said outer housing and said bellows housing.

It A pressure actuated switch and plug assembly as claimed in claim 1 in which said base includes insulative plastic surrounding and frictionally interfitted with the exterior of said communication tube to connect said communication tube to extend rigidly from said base, said communication tube having an O-ring therearound to seal within said compressed gas conduit.

References Cited UNITED STATES PATENTS 2,557,929 6/1951 Baak 317157 2,961,507 11/1960 Higgs 200-83 FOREIGN PATENTS 139,438 4/ 1946 Australia.

BERNARD A. GILHEANY, Primary Examiner. H. B. GILSON, Assistant Examiner. 

1. A PRESSURE ACTUATED SWITCH AND PLUG ASSEMBLY SUPPORTING THEREIN, A SWITCH ARM HAVING A PIVOTED END, UPPER AND LOWER, SPACED APART CONTACTS, AND AT LEAST FIRST, SECOND AND THIRD CONDUCTORS EXTENDING RESPECTIVELY FROM SAID PIVOTED END AND FROM SAID CONTACTS, AND A SNAP ACTION PLUNGER HAVING OUTWARDLY A CONTACT POINT, A BELLOWS HOUSING HAVING A BELLOWS ACROSS THE HOUSING INTERIOR, A BORED GLAND ADJUSTABLY THREADABLE DOWNWARDLY INTO SAID BELLOWS HOUSING TO BEAR UPON A SPRING PROVIDED BETWEEN SAID GLAND AND SAID BELLOWS, A CLOSURE PLUNGER EXTENDING SEALABLY THROUGH SAID GLAND BORE, AN INSULATIVE BASE TO RECEIVE SAID BELLOWS HOUSING THEREIN, SAID CONDUCTORS CONNECTING WITH RESPECTIVE CONDUCTOR PRONGS EXTENDING FROM SAID BASE, AN INSULATIVE PLUG SUPPORTED TO CONNECTABLY RECEIVE SAID PRONGS THEREIN TO CONTACT RESPECTIVE PREDETERMINED CIRCUIT COMPLETING MEANS EXTENDING THEREFROM, A COMPRESSED GAS CONDUIT CONNECTING UPWARDLY THROUGH SAID BASE INTO SAID BELLOWS HOUSING, A COMPRESSED GAS COMMUNICATION TUBE SUCCESSIVELY CONNECTED WITH SAID BELLOWS HOUSING AND WITH SAID BASE AND EXTENDING DOWNWARDLY THEREBELOW INTO SAID COMPRESSED GAS CONDUIT, WHEREBY SAID BELLOWS MOVES UPWARDLY AND DOWNWARDLY RESPONSIVE RESPECTIVELY TO INCREASE AND DECREASE OF COMPRESSED GAS PRESSURE SO THAT SAID CLOSURE PLUNGER RESPECTIVELY CONTACTS SAID POINT TO URGE SAID SNAP ACTION PLUNGER TO PIVOT SAID ARM 